9256( 2) - 05/31/01 13:52 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9256 Version: 2 Check-in Date: 31-May-2001 13:52:05 1.Proposal Title: Methane Quad Filter Check ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle CAL/WF2 10 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: John Biretta Space Telescope Science Institute CoI: Erich Karkoschka University of Arizona N CoI: Sylvia Baggett STScI N ------------------------------------------------------------------------------------ 5. Abstract Verify FQCH4N-D methane filter characteristics. ------------------------------------------------------------------------------------ Observations Description ------------------------ Based on results from Jupiter and Uranus archival WFPC2 data, the extended wings of the methane filter transmission curve appear to vary across the field of view. While this is unimportant for objects with flat spectra, it can have a major impact on photometry of objects with methane bands, where a significant fraction of photons comes from the wings. To provide data to check the methane filter, a set of eight 40-sec Saturn images will be taken in a 3x3 grid around the FQCH4W3 methane quad filter aperture (one of the 9 positions falls outside of the filter). The magnitude and direction of the effect will be quantified by comparing results from the rings of Saturn (flat spectrum) to results from Saturn itself (deep methane band spectrum). This proposal is an outsourcing candidate. Gain 15 is used to prevent saturation of the rings. Ring B saturates after 20 sec at opposition, after 30 sec at phase angle 4 degrees, and after 35 sec at phase angle 6.5 degrees, so 26 sec exposure times will be used along with phase angle restricted to 4-7. The 26 sec exposure time still provides ~300 counts on the planet which is sufficient. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 9256( 2) - 05/31/01 13:52 - [ 2] TARGET LIST Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: SATURN ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: PLANET SATURN ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD=SATURN | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | PHASE OF SATURN FROM EARTH BETWEEN 4 7 | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = -0.1+/-0.1 | approximate V mag is for SURF(V) = 6.9+/-0.1 | planet+rings during Sep-Dec 2001; | surface brightness is for | illuminated area of disk | ------------------------------------------------------------------------------------------------------------------------------------ 9256( 2) - 05/31/01 13:52 - [ 3] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: NOTES: Saturn phase angle must be between 4 and 7, as specified in solar system target Window requirement. POS TARGS outside of aperture are intentional. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 21, 52 ------------------------------------------------------------------------------------------------------------------------------------ 20 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 4, 42 ------------------------------------------------------------------------------------------------------------------------------------ 30 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG -13, 32 ------------------------------------------------------------------------------------------------------------------------------------ 40 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 4, 22 ------------------------------------------------------------------------------------------------------------------------------------ 50 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG -13, 12 ------------------------------------------------------------------------------------------------------------------------------------ 60 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 4, 2 ------------------------------------------------------------------------------------------------------------------------------------ 70 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG -13, -8 ------------------------------------------------------------------------------------------------------------------------------------ 80 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 4, -18 ------------------------------------------------------------------------------------------------------------------------------------ 90 SATURN WFPC2 IMAGE FQCH4W3 FQCH4N 8929 CR-SPLIT=NO,ATD-GAIN=15 1 26 S POS TARG 21, -8 ------------------------------------------------------------------------------------------------------------------------------------ 9256( 2) - 05/31/01 13:52 - [ 4] Summary Form for Proposal 9256 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures FQCH4W3 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ATD-GAIN=15 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category CAL/WF2 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements POS TARG 21, 52 POS TARG 4, 42 POS TARG -13, 32 POS TARG 4, 22 POS TARG -13, 12 POS TARG 4, 2 POS TARG -13, -8 POS TARG 4, -18 POS TARG 21, -8 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements FQCH4N ------------------------------------------------------------------------------------------------------------------------------------ Target Names SATURN ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 8929 ------------------------------------------------------------------------------------------------------------------------------------